TMCnet News
the technology gap that can leave planes invisible [Pretoria News (South Africa)](Pretoria News (South Africa) Via Acquire Media NewsEdge) Call emergency services from the side of the road, and global positioning system (GPS) satellites can tell dispatchers exactly where to send help. Airline passengers have access to detailed maps that show exactly where they are during their flight. Hop on to wi-fi and Google knows whether you're logging on from Lima or London. So how is it that we have no idea where Flight 370 has gone? The answers offer a look at current technology's limitations. What happened to radar? Radar extends only so far. Air traffic controllers typically use radar to monitor a flight's progress. That's all very well over land. But radar also has a limited range, and you can't put a radar station in the middle of the ocean. So pilots often have to stay in contact through other means, such as periodic radio check-ins. In between check-ins, controllers have only a general idea of where a plane is and where it's headed. Flight 370 may have been in contact with military radar in its final moments - but whether a civilian air traffic controller knew where it was is less clear. Flight 370's transponder signal was lost just as the plane was to enter Vietnamese air space - and because transponders are meant to work with radar, that suggests the plane was close enough to shore to be on somebody's screen. Could somebody have turned off the aircraft's transponder? That's a tricky question. Pilots can send coded messages over the transponder in an emergency. But we're not sure what happened to the transponder in this case. We don't know if anybody tried to tamper with it. But why would they? Reports suggest nobody on the plane made a distress call of any kind - no radio transmission, nothing. That implies there wasn't time to cry for help in the midst of a technical breakdown or a violent struggle. If that's the case, it's not likely an attacker - if there was one - would try messing with the transponder while still trying to gain control of the aircraft. What about passengers' cellphones? Could they be tracked? The reason you can be tracked on land is because your phone is constantly talking to cell towers. No towers? No service, and therefore no location. While you're in the air, there's not much opportunity to use your cellular network - although that's changing in Europe and may soon begin to change in the US, too. Technology now enables the use of cellular networks if a plane carries a special base station that sends communications to a commercial satellite, which then relays it to the ground. But adoption will be voluntary among airlines. Don't phones often carry GPS chips? Yes, many cellphones do have GPS. But it's not the kind you'd find in a car. Cellphones typically rely on a kind of "assisted" GPS - one that requires a constant data connection. Without wi-fi or a cellular tower, you're not able to connect with the satellite. Did Flight 370 have wi-fi? Wi-fi would almost certainly have helped. Mobile devices on the plane would have been communicating with the internet right up until its other communications systems went down. But Malaysia Airlines does not appear to offer in-flight wi-fi. What other technologies might have helped maintain a fix? The US Federal Aviation Administration wants to move to a next-generation air traffic control system that uses GPS satellites to keep tabs on planes. It's called, Next Gen. Satellites have a distinct advantage over radar - a technology that dates from World War II - in that they can monitor wide swathes of territory, including oceans. But this system is still years away. Malaysia Airlines would not have been covered. Someday, however, a worldwide version of Next Gen might prevent any future Flight 370s. US officials have examined spy satellite imagery of the region and have turned up no clues about the fate of the plane. - Washington Post Pretoria News (c) 2014 Independent Newspapers (Pty) Limited. All rights strictly reserved. Provided by Syndigate.info, an Albawaba.com company |